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<h1>DataSetParam</h1>

<p>Describes an input and/or output parameter of the data 
set query.</p>

<h3>Description</h3>

<p>The data set parameter definition element describes the 
parameters of the data set query. A parameter can be input only, output only, 
or both. </p>

<h3>See Also</h3>

<p>The Parameter Definitions section above for the rules to 
identify a parameter by name vs. position</p>

<h2 class="property">name</h2>

<p>The name of the parameter.</p>

<h3>Description</h3>

<p>The name of the parameter. Required. Must be unique 
within a data set definition.</p>

<h3>See Also</h3>

<p>The Parameter Definitions section above for the naming rules</p>

<h2 class="property">position</h2>

<p>The 1-based position of the parameter, as defined by 
the underlying driver.</p>

<h3>Description</h3>

<p>The 1-based position of the parameter, as defined by the 
underlying driver. Required for data sets that identify input parameters by 
position instead of name. Ignored otherwise.</p>

<h3>See Also</h3>
<h2 class="property">dataType</h2>

<p>The optional data type of the parameter.</p>

<h3>Choices</h3>
<ul>
<li>string: Arbitrary Unicode text.</li>

<li>decimal: Any type of number 
    including currency. Fixed decimal, arbitrary precision.</li>

<li>float: A scientific amount 
    using the usual floating point notation.</li>

<li>dateTime: A date, time or 
    combination of date and time.</li>

<li>integer: A whole number.</li>

</ul>
<h3>Description</h3>
<p>The optional data type of the parameter. Required only 
for data sets that require this information. Complex data set parameter data 
types, such as structure or table parameters of a query, are reserved for future 
releases, and are not listed in the Choices specification. </p>

<h3>See Also</h3>
<h2 class="property">isOptional</h2>

<p>Whether the report must provide a value for the input parameter.</p>

<h3>Description</h3>
<p>If false, the report must provide a value for the input 
parameter. If true, the value is optional. This property value is not relevant 
if the <span style="font-family: Courier New">defaultValue</span> property is 
defined with a value.</p>

<h3>See Also</h3>
<h2 class="property">defaultValue</h2>

<p>The BIRT expression that defines the default value of the input parameter.</p>

<h3>Description</h3>
<p>The expression that gets evaluated and its resulting 
value assigned as default value of the input parameter. The default value 
expression, if defined, is automatically bound to the parameter only if no 
explicit parameter binding is defined in the data set and its corresponding 
report parameter. </p>

<h3>See Also</h3>
<p>Data Set <span style="font-family: Courier New"> 
ParamBinding</span> structureReport Item <span style="font-family: Courier New"> 
paramBindings</span> property</p>

<h2 class="property">allowNull</h2>

<p>Whether a null value is allowed for this parameter.</p>

<h3>Description</h3>
<p>If true, the parameter value can be null. If false, the 
value cannot be null.</p>

<h3>See Also</h3>
<h2 class="property">isInput</h2>

<p>Whether the parameter is of input mode.</p>

<h3>Description</h3>
<p>Indicates whether the parameter is of input mode. If 
true, this is an input parameter; if false, this is not an input parameter.</p>

<h3>See Also</h3>
<h2 class="property">isOutput</h2>

<p>Whether the parameter is of output mode.</p>

<h3>Description</h3>
<p>Indicates whether the parameter is of output mode. If 
true, this is an output parameter; if false, this is not an output parameter.</p>

<h3>See Also</h3>
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